I don't know.
I am nineteen (although I keep forgetting I'm no longer eighteen).
I can be more mature in some respects, like I never really had a 'teen' period of needing to be different, staying out late, rowing with parents the whole time, but in other respects I'm quite immature - I like playing silly 'poking' games with my friend (also half-mature, half-immature 19-year-old) and we like messing about and saying and doing things that people think we're weird for doing when it's just fun, like messing around on the floor playing fun, frantic improvised games with clothes pegs
I kind of feel like I switch between the two - adult/child.
I don't know about emotionally because I don't know what everyone else's emotions feel like to them or how they differ.
I don't know which category this might come under, but people I work with tend to think of me as being a bit behing in the growing up process - they keep telling me I ought to have done such-and-such by now or I'm old enough to do such-and-such which is annoying, because I can't make myself any different.
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I don't have Aspergers, I'm just socially inept
Dodgy circuitry! Diagnosed: Tourette syndrome. Suspected: auditory processing disorder, synaesthesia. Also: social and organisation problems. Heteroromantic asexual (though still exploring)